Electric-lamp globe



.WITNE5E5 (No Model.)

G.D.BU8T0N.

,ELECTRIC LAMP GLOBE.

No. 288,157. Patented July 81, 1888.

Figs.

lun/ENTER t' y"Uilfliiri STATES ATENT OFFICE.

enonenn; BURTON, or Nnw irswicir, NEW HAMrsHinE.

ELECTRIC-LAMP GLOBE.

SPECIFICATION formingpart of Letters Patent No. 282,157, dated July 31, 1883.

Application tiled Febrnaryl, 1885. (Noinodel.)

To all whom vit may concern,.-

Be it known that I, GEORGE D. BURroN, of New` Ipswich, county of Hillsborough, State of New Hampshire, have invented an Improvement inGlobes for Electric Lamps, of which the following descriptionin connection with the accompanying drawings, is a specification, like letters on the drawings rep resenting like parts.

My invention relatesto a globe for inclosing a lamp, (shown in this instance as an electric-arc lamp,) having for its object the production of a strong durable globe capable of withstandingconsiderable pressure and not being injured by sudden changes in temperature. The globe consists, essentially, of plates of mica mounted in a suitable frame-work, glass be` ing preferably employed `for the framework on account of its transparency, and the said joints being made substantially airtight. A globe of this character maybe employed, in connection with an arc-lamp, to prevent a continuous supply o f air from reaching the carbons, so that after they have once consumed the oxygen that is inclosed in the globe, or converted it to carbonio-acid gas, there will be very little, if any, further combustion of the carbon, and they will consequentlylast much longer than when'burned in the ordinary open globes. The materialof which the globe is composed will be capable of withstanding the high temperature to which the gases confined in it may be raised,V and is not liable, as are the ordinary glassglobes, to crack under sudden changes fin temperature, or from a large difference between the temperature `within and without it. If .desired, the' air may be exhausted, or the globemay be filled with nitrogen or other gas incapable of supporting combustion; `but this will not be generally necessary, asthe small amount of oxygen in the air lling the globe will be sufficient to consume only a slight amount of carbon, the essential point being that there is not contained a supply of oxygen tothe carbons, as isthe case when the usual open globes are employed, so that their combustion will be greatly iinpeded, if not wholly checked. e

Figurel is a front elevation of an electric lamp provided with a globe embodying this invention; Fig. H2, ahorizontal section thereof on a larger scale; Fig. 3, a vertical section on dotted lines a: m, Fig. 2 5 and Fig. et, a perspective view of one of the mica plates.

`The globe is shown in this instance as employedin connection with an electric lamp of ordinary construction, composed of framework a, lhaving the lower or negative carbon, b, rigidly connected with the lower portion vof the said frame-work, and the upper carbon, c, controlled by a regulator, of any usual construction, contained in the case d, mounted on the upper portion of the said frame-'work c. The said globe is composed of top and bottom plates, e f, which may be of metal, and side plates, h, fitted in suitable grooves or sockets in the said plates e and f, as shown in Fig. 3, and fastened together where their side edges meet by vertical-framing or rods i, fastened at their ends to the said plates c f, the said vertical rods c' being preferably of glass, so as not to obstruct the rays of light. The plates e f it, with the rods or framing i, thus constitute a chamber which may be essentially air-tight. The upper plate, e, is provided with an'open- 75 ing of sufficient size to admit of the free movement of the carbon c therethrough. The upper plate, e, is connected with the regulatingcase d by tube m, so as to prevent the H admission of air around the carbon c, the regulat- 8o ing-case itself being also made essentially airtight. It will be seen that by employing an air-tight inclosing case or globesuch as hereindescribed-thecarbons do not receive` the usual continuous supply of air or oxygen for 85 producing rapid` combustion, and that if the air is exhausted from the said globe, or if it is filled with nitrogen, or other gas incapable of combustion, or even when filled with air, the oxygen will `very soon be consumed, so 90 that in any case there will be no free combustion of the carbons, and their durability will consequently be greatly increased.

It is not essential, as in the case of an in-4 candescent light, that the supply of oxygen should be ej irely removed; but by preventing its free alnl continuous supply the rapidity of consumption of the carbons is greatly reduced. A globe composed of mica, and constructed as herein described, will be capable roo of withstanding the great variations in tem perature and pressure to which `it is exposed when unprotected upon the outside and containing a body of highly-heated 'gas upon its adapted for use on oil-lamps, and composedof mica sides, metal connecting-ribs therefor, (which are not air-tight and break up the diffusion of light,) a metal upper rim, and ametal base, such being public property.

I claim- 1. A globe for lamps composed of mica side plates united by transparent air-tight joints,

and suitable top and bottom plates, substan- 1 tially as shown and described.

2. In a globe, the combination, with the top and bottom plates, of side plates composed of 2o mica, and vertical transparent rods supporting the said side plates along their meeting edges, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two sub- 25 scribing Witnesses.

GEO. D. BURTON.

Witnesses:

J os. I. LIVERMORE, WV. H. SIGsToN. 

